Nec 1300a cyclic redundancy errors

hello everybody. i have a nec 1300a and after 6o dvds and three months of using it I get cyclic redundancy errors on the media i’m burning on the nec. I have checked it with severaltypes of media like philips primedisc mam and + and -. The firmware is the one it came in and i use nero 6. The movies i burn cannot be copied after the burning due to messages i get “cyclic redundancy error” or played on power dvd, windvd. Please help, i would i apreciate it!